How to Boost L. reuteri Levels for Improved Gut Health

December 9, 2025 •

4 min read

Recent studies underscore the significant role of the gut microbiome in overall wellness, highlighting beneficial bacteria like L. reuteri. Maintaining a robust population of this specific probiotic is crucial for digestive balance, and you can learn how to boost L. reuteri through several effective strategies.

Quick Summary

Strategies to increase L. reuteri populations involve consuming specific fermented foods, using targeted supplements, and eating prebiotic-rich fiber. Supporting the gut's overall ecosystem is also key to creating an environment where this beneficial bacteria can thrive.

Key Points

Supplements: Utilize probiotic supplements with specific, clinically-studied strains like DSM 17938 or ATCC PTA 6475 for a guaranteed, high-potency dose.
Fermented Foods: Consume certain fermented foods like homemade yogurt prepared with an L. reuteri starter culture, as well as some sauerkraut and kimchi.
Prebiotic Fiber: Incorporate a variety of prebiotic-rich foods such as garlic, onions, bananas, and whole grains to nourish and promote the growth of existing gut bacteria.
Harmful Habit Reduction: Limit the consumption of processed foods, excessive sugar, and unnecessary antibiotics, all of which can negatively impact the gut microbiome.
Homemade Yogurt: Create your own highly potent L. reuteri yogurt at home using a specific starter culture and fermenting for 24-36 hours at 100°F.
Diverse Diet: Maintain a diet rich in diverse plant-based foods to ensure a broad spectrum of prebiotic fiber and nutrients that support overall microbiome diversity.

Understanding L. reuteri and Its Importance

Limosilactobacillus reuteri, commonly known as L. reuteri, is a probiotic bacterium naturally found in the human gut, urinary tract, and skin. It is valued for its ability to produce reuterin, a powerful antimicrobial substance that can inhibit the growth of harmful pathogens and help create a balanced gut environment. A healthy population of L. reuteri has been linked to numerous benefits, including supporting digestion, managing specific gastrointestinal issues like infantile colic and constipation, and potentially influencing the gut-brain axis.

Method 1: Increase L. reuteri Through Diet

Diet is a powerful tool for naturally encouraging the growth of beneficial gut bacteria. Two primary dietary approaches focus on directly introducing the probiotic or feeding it with the right nutrients.

Fermented Foods Containing L. reuteri

Not all fermented foods contain L. reuteri, so it's important to choose sources carefully. Some common options include:

Cultured Dairy: Certain yogurts and kefir specifically cultured with L. reuteri strains. Always check the label to ensure the strain is included. Homemade yogurt can also be fermented with an L. reuteri starter culture for higher concentrations.
Fermented Vegetables: Some types of naturally fermented sauerkraut and kimchi may contain L. reuteri, but this is not guaranteed unless the starter culture is known. For reliable results, a homemade approach is best.
Sourdough Bread: The natural fermentation process used in some sourdough breads can introduce lactobacilli, including L. reuteri, into the bread.

Feeding the Gut with Prebiotic Fiber

Prebiotics are non-digestible fibers that act as food for probiotics. Consuming these foods helps create a hospitable environment for L. reuteri to flourish. Key prebiotic sources include:

Garlic and Onions: These alliums contain inulin, a type of fiber that supports gut microbes.
Bananas: Especially unripe or green bananas, contain resistant starch that ferments in the large intestine.
Artichokes and Asparagus: Excellent sources of fructans and inulin.
Whole Grains: Oats, barley, and other whole grains provide fermentable fiber.

Method 2: Use Targeted Probiotic Supplements

For a more direct and potent approach, specific probiotic supplements are available. Supplements offer strain specificity and a guaranteed dosage, often containing billions of colony-forming units (CFUs).

Selecting the Right Supplement

When choosing a supplement, look for specific, clinically-studied strains of L. reuteri. Some of the most common and well-researched strains include DSM 17938, ATCC PTA 6475, and ATCC PTA 5289. These strains have different benefits and applications, from reducing infantile colic to improving oral health. It's also important to follow dosage instructions and be aware that recent classifications have renamed the bacterium Limosilactobacillus reuteri, though many labels still use the older name.

Method 3: Adopt a Gut-Friendly Lifestyle

Beyond diet and supplements, certain lifestyle factors are critical for a thriving gut microbiome.

Avoid Gut-Damaging Substances

Reduce Processed Foods and Sugar: Diets high in processed foods and refined sugars can harm beneficial gut bacteria and promote the growth of harmful organisms.
Limit Excessive Alcohol: Overconsumption of alcohol can disrupt the delicate balance of the gut microbiome.
Avoid Unnecessary Antibiotics: Antibiotics, while sometimes necessary, can indiscriminately wipe out both good and bad bacteria. Discuss with your doctor minimizing their use where possible.

Promote Gut Microbiome Diversity

Eat a Diverse Diet: A wide variety of plant-based foods, including fruits, vegetables, nuts, and seeds, provides a spectrum of prebiotic fibers that nourish a diverse microbial community.
Manage Stress: Chronic stress can negatively impact the gut-brain axis and the overall microbiome. Practices like meditation, exercise, and adequate sleep can help.

Comparison Table: L. reuteri Sources


Feature	Probiotic Supplements	Fermented Foods (e.g., Homemade Yogurt)
Strain Specificity	High. Labels list specific, tested strains (e.g., DSM 17938).	Can be high if using a specific starter culture.
Dosage Control	High. Clearly labeled CFUs (colony-forming units) allow for precise dosing.	Variable. Bacterial counts depend on fermentation time and temperature, making exact dosage uncertain.
Natural Context	Lower. Bacteria are isolated and delivered in a capsule or powder.	High. Consumed as part of a whole food matrix, which may offer additional nutrients.
Cost	Can be expensive, especially for high-potency, specific-strain products.	Potentially more cost-effective for long-term use.
Convenience	High. Easy to take on a daily basis.	Variable. Requires time and effort for preparation, but can be incorporated into daily meals.

Conclusion

Boosting L. reuteri levels is a multi-faceted endeavor that combines targeted dietary choices with smart supplementation and a health-conscious lifestyle. By incorporating specific fermented foods like homemade L. reuteri yogurt and increasing your intake of prebiotic fibers from diverse plant sources, you can naturally cultivate a healthier gut environment. When a more concentrated or specific approach is needed, high-quality probiotic supplements containing clinically studied strains like DSM 17938 can be highly effective. Ultimately, supporting your gut is a long-term strategy, and a holistic approach focusing on these elements offers the best path to maximizing your L. reuteri population and reaping the associated digestive benefits. For more in-depth scientific literature on L. reuteri, consult resources like the National Institutes of Health.

Frequently Asked Questions

The most targeted and potent ways to get L. reuteri are through high-quality probiotic supplements containing clinically tested strains, or by making homemade yogurt using a specific L. reuteri starter culture.

Foods confirmed to contain L. reuteri are often dairy-based, such as certain yogurts and kefir that are specifically cultured with this strain. Some naturally fermented vegetables like sauerkraut and kimchi, as well as some sourdough bread, may also contain it.

Prebiotics are non-digestible fibers that serve as food for beneficial gut bacteria, including L. reuteri. Consuming prebiotic-rich foods like garlic, onions, bananas, and artichokes can help nourish and sustain your existing L. reuteri population.

Look for specific, clinically studied strains like DSM 17938 (often used for gut health) and ATCC PTA 6475, which are commonly available and well-researched for their benefits.

Yes, you can make your own L. reuteri yogurt at home by using a specific starter culture and fermenting it over a longer period (24-36 hours) to achieve a higher concentration of the bacteria.

Yes, avoiding or reducing intake of processed foods, excessive sugars, and unnecessary antibiotics can help maintain a healthy gut environment where beneficial bacteria like L. reuteri can flourish.

The species L. reuteri was reclassified in 2020 under the new genus Limosilactobacillus. Both names refer to the same beneficial bacterium, and some product labels may still use the older name.